Move liblog headers to system/core/include/log

Move the liblog headers to log/ instead of cutils/ to complete
the separation of libcutils and liblog.  cutils/log.h still
exists and includes log/log.h in order to support the many existing
modules that use cutils/log.h.

Change-Id: I2758c9f4aedcb809ca7ba8383d0f55041dd44345
diff --git a/adb/Android.mk b/adb/Android.mk
index 36f595b..721b48d 100644
--- a/adb/Android.mk
+++ b/adb/Android.mk
@@ -130,7 +130,7 @@
 LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT_SBIN)
 LOCAL_UNSTRIPPED_PATH := $(TARGET_ROOT_OUT_SBIN_UNSTRIPPED)
 
-LOCAL_STATIC_LIBRARIES := libcutils libc libmincrypt
+LOCAL_STATIC_LIBRARIES := liblog libcutils libc libmincrypt
 include $(BUILD_EXECUTABLE)